The present invention relates generally to flexible reclosable containers and more particularly to the manufacture of such containers for use in what is commonly called form, fill and seal packaging systems.
The use of flexible containers having reclosable fasteners either integrally formed in the sidewalls thereof or heat sealed thereto is widely known, as shown in U.S. Pat. Nos. 3,198,228, Naito; 3,338,284 Ausnit; and, 4,101,355, Ausnit. Similarly, the use of such containers for form, fill, seal packaging systems may be seen in U.S. Pat. No. 4,355,494, Tilman, and U.S. Pat. No. 4,617,683, Ausnit. However, in the '494 patent of Tilman, individual reclosable fastener profiles are attached to the lateral edges of a flat continuous web of film utilizing adhesive. As a result, after the web is formed into a tube, the individual profiles must be brought together and interlocked. In addition, the adhesive must be maintained under compression for a sufficient period in which to set. The speed of manufacture is thereby reduced. In the '683 patent of Ausnit, sections of fastener strips are extended transversely across the web and heat sealed thereto. Again, the speed of manufacture is thereby reduced.
Accordingly, it is an object of the present invention to provide an apparatus and method for manufacturing flexible reclosable containers in which the fastener profiles are heat sealed within the longitudinal seal of the container.
It is an additional object of the present invention to provide an apparatus for the high speed manufacture of flexible reclosable form, fill, seal containers.